CRF100 jetting?

[Terez]

Hi there

Just bought an 05 CRF100 for my son.

It is very cold blooded and hard to start when cold.

I assume it is the typical factory lean carburetion and corked condition?

Anyone have a dialed in setup for the pilot and main and or airbox/exhaust mods to make it start/run smoother?

I am thinking 1 up on the pilot jet and main and open the airbox lid a bit?

What about shimming the needle?

What can you do to the stock muffler to open it a bit without completely gutting it?

Thanks

[hornetgod13]

My son's bike will start on the first or second kick now that I've rejetted it. I removed the screen from the inside of the air filter module, installed a UNI foam filter, cut two large holes in the top of the airbox, and installed a FMF Powercore IV full exhaust. The current bike jetting is 38K pilot, 105K main, fuel screw is 1 1/2 turns out, and the clip is lowered a slot on the needle.